Lack of Power/Sluggish/Spongy

SYMPTOM DESCRIPTION:


Engine delivers less than expected power. Little or no increase in speed when accelerator is pushed down part way.


POSSIBLE CAUSE ACTION


CHARGING SYSTEM MALFUNCTION - Check Battery voltage.

- Check Alternator output voltage.




IGNITION SYSTEM MALFUNCTION - Scope check Ignition System

- Check IGNITION COIL for proper output voltage.

- Check SPARK PLUGS for proper spark duration. Remove spark plugs, check for fuel fouled plugs, cracks, wear, improper gap, burned electrodes, or heavy deposits. Replace as necessary.

- Check SECONDARY CIRCUIT for abnormal firing Kv, crossfire between spark plugs (distributor cap, spark plug wires), and proper plug wire routing.

- Check IGNITION TIMING for excessive spark retard.



ENGINE MECHANICAL MALFUNCTION - Check COMPRESSION Perform a compression check, and cylinder leakage test, look for weak cylinders.

- Check for VACUUM LEAKS inspect Intake manifold, gasket(s), and hoses.

- Check exhaust system for leaks, restriction, or damage.

- Check for incorrect valve timing.



EMISSIONS COMPONENT MALFUNCTION - Check EGR valve for binding or sticking in the open position.

- Check EGR Transducer for proper operation.

- Check for plugged or contaminated Catalytic Converter.



FUEL SYSTEM MALFUNCTION - Check for incorrect Air-Fuel mixture, O2 Sensor, perform injector balance test, inspect regulator operation (check vacuum line and return hose), check fuel pressure.

- Check for defective Fuel Pump Ballast Bypass Relay.

- Check plugged or restricted Fuel Filter.

- Check plugged or restricted Air Filter.

- Check fuel quality.




TRANSMISSION MALFUNCTION - Check for proper transmission shift points.

- Check for proper Torque Converter Clutch (TCC) operation.